How to get Accurate Scaling When Making New Objects?
Scale is a multiplier that is applied to the local size of the mesh to calculate the global size and the dimensions of the object. This is not what you want.
You're probably looking for the dimensions of the object or better the edge lengths of the mesh.
In Object Mode, you can see and edit the dimensions of the object in the sidebar (&quot;N-panel&quot;, press N in the view to open it). With Ctrl+A, then Apply Scale you can apply the scale, what resets it to 1. See here: Dimension vs scale
In Edit Mode, you can display the lengths of the edges. You need to activate it in the Overlays drop-down menu. There you can switch between Global and Local and you will see the impact of the scale. Have a look here for screenshots: Why do measurements change when switching from Global to Local in edit mode?